Longitudinal assessment of maternal micronutrients (folate and vitamin B12) and homocysteine levels in women who develop gestational diabetes mellitus.

Background: Micronutrients (folate and vitamin B₁₂) and homocysteine are key components of the one-carbon metabolism and literature on the associations of these micronutrients with the pathophysiology of gestational diabetes mellitus (GDM) is unclear. The current study aims to examine the levels of these micronutrients across pregnancy in women who develop GDM and compare them with non-GDM women.

Methods: A total of 200 pregnant women (100 Non-GDM and 100 GDM) were included in the study and blood samples were collected at 4 different time intervals throughout pregnancy (Visit-1 = 11-14 weeks, Visit-2 = 18-22 weeks, Visit-3 = 26-28 weeks, and Visit-4 = at delivery).

Results: Vitamin B₁₂ levels at V3 and V4 (p = 0.031 and p = 0.001) and folate levels from V2, till delivery (p < 0.01 for V2, V3 and p = 0.025 for V4) were higher in GDM as compared to non-GDM. However, homocysteine levels were lower at all time points across gestation (p < 0.01 for all) in women with GDM. Intake of vitamin B₁₂ & folate rich foods was comparable in GDM and Non-GDM women. Also, the percentage of GDM women who took vitamin B₁₂ supplements was comparable between groups, while folate supplements were higher V1 (p < 0.01) in GDM women.

Conclusions: Elevated micronutrients and lower homocysteine levels in GDM women necessitate more research for better understanding the role of these one carbon nutrients in the etiology of GDM and emphasizes the need to establish the optimum maternal vitamin B₁₂ and folate levels for fetal development.